Gold has many exciting properties: In addition to its rarity, its unusually high weight is particularly fascinating. In addition, there is its warm tone and its everlasting luster, since the precious metal does not corrode. Finally, it can be worked mechanically very well, so gold has been used for jewelry and ritual objects since time immemorial.
Pure gold (24 carats/999 gold) is rarely considered for watch cases, as it would be too soft and susceptible to scratching in this form. However, gold can be combined with other metals to form very advantageous alloys. This results not only in greater hardness of the material, but also in very aesthetic shades. In the periodic table, gold belongs to the copper group with copper and the precious metal silver. These are also the metals with which gold is usually alloyed.
18-carat or 750 rose gold, for example, contains 75% fine gold, more than 20% copper and some proportions of silver. The case of the Robert Mühle Auf/Ab GOLD was made from this alloy. 18-carat yellow gold, on the other hand, is used in the Teutonia IV Edition Gold: the alloy consists essentially of 75% fine gold and equal parts copper and silver (approx. 12.5% each).